It's going to be hard to delay Renaissance as one block, essentially because there is a really important continuation from Italian medieval culture from the Trecento, but parts of it for instance technological-cultural advances as printed press, or the development of an extra-universitary scholarship could.
We'd then go for a different Renaissance of the XVth, maybe to the point it would be considered as part of what we call pre-Renaissance rather than a specific rupture.But unless for going for several PoDs (including somes going back to the Renaissance of the XIIth) you won't be able to delay or change everything IMO.
Now the effects really depend from what should be delayed, what should be kept : and ideas?